 
<template>
  <div class="home-page">
    <div class="banner">
      <div class="container">
        <h1 class="logo-font">conduit</h1>
        <p>A place to share your knowledge.</p>
      </div>
    </div>
    <div class="container page">
      <div class="row">
        <div class="col-md-9">
          <div class="feed-toggle">
            <ul class="nav nav-pills outline-active">
              <li class="nav-item">
                <nuxt-link
                  v-if="user"
                  class="nav-link"
                  :class="{
                  active:tab === 'your_feed'
                }"
                  exact
                  :to="{
                  name:'home',
                  query:{
                    tab:'your_feed'
                  }
                }"
                >Your Feed</nuxt-link>
              </li>
              <li class="nav-item">
                <nuxt-link
                  class="nav-link"
                  exact
                  :class="{
                  active:tab === 'global_feed'
                }"
                  to="/"
                >Global Feed</nuxt-link>
              </li>
              <li class="nav-item" v-if="tag">
                <nuxt-link
                  class="nav-link"
                  :class="{
                  active:tab === 'tab'
                }"
                  exact
                  :to="{
                  name:'home',
                  query:{
                    tab:'tab',
                    tag
                  }
                }"
                ># {{ tag }}</nuxt-link>
              </li>
            </ul>
          </div>
          <div class="article-preview" v-for="article in articles" :key="article.slug">
            <div class="article-meta">
              <nuxt-link
                :to="{name:'profile',
              params:{
                username:article.author.username
              } }"
              >
                <img :src="article.author.imgae" />
              </nuxt-link>
              <div class="info">
                <nuxt-link
                  :to="{name:'profile',
              params:{
                username:article.author.username
              } }"
                >{{article.author.username}}</nuxt-link>
                <span class="date">{{article.createdAt | date('MMM DD, YYYY')}}</span>
              </div>
              <button
                class="btn btn-outline-primary btn-sm pull-xs-right"
                @click="onFavorite(article)"
                :disabled="article.favoriteDisabled"
                :class="{active:article.favorited}"
              >
                <span >
                  <i class="ion-heart"></i>
                  {{ article.favoritesCount }}
                </span>
              </button>
            </div>
            <nuxt-link
              :to="{
              name:'article',
              params:{
                slug:article.slug
              }
            }"
              class="preview-link"
            >
              <h1>{{ article.title }}</h1>
              <p>{{ article.description }}</p>
              <span>Read more...</span>
            </nuxt-link>
          </div>

          <!--  分页 -->
          <nav>
            <ul class="pagination">
              <li class="page-item" :class="{active : i === page}" v-for="i in totalPage" :key="i">
                <nuxt-link
                  class="page-link"
                  :to="{
                  name:'home',
                  query: {
                    page: i,
                    tag: $route.query.tag
                  }
                  }"
                >{{ i }}</nuxt-link>
              </li>
            </ul>
          </nav>
        </div>

        <div class="col-md-3">
          <div class="sidebar">
            <p>Popular Tags</p>
            <div class="tag-list">
              <nuxt-link
                v-for="(item, i) in tags"
                :key="i"
                :to="{name: 'home',
              query: {
               tag:item,
               tab:'tab'
              }}"
                class="tag-pill tag-default"
              >{{item}}</nuxt-link>
            </div>
          </div>
        </div>
      </div>
    </div>
  </div>
</template>

<script>
import {
  getArticles,
  getTags,
  getArticlesFee,
  addFavorite,
  delFavorite,
} from "@/api/home";
import { mapState } from "vuex";
export default {
  name: "home",
  async asyncData({ query }) {
    try {
      const page = +query.page || 1;
      const tab = query.tab || "global_feed";
      const tag = query.tag || "";
      const limit = 20;
      const getArticlesAll = tab === "your_feed" ? getArticlesFee : getArticles;
      const [data, tagdata] = await Promise.all([
        getArticlesAll({
          limit,
          tag,
          offset: (page - 1) * limit,
        }),
        await getTags(),
      ]);
      data.articles.forEach(element => {
        element.favoriteDisabled = false
      });
      return {
        ...data,
        ...tagdata,
        tab,
        tag,
        limit,
        page,
      };
      //  console.log(data ,'------')
    } catch (error) {
      console.log(error);
    }
  },
  watchQuery: ["page", "tag", "tab"],
  computed: {
    ...mapState(["user"]),
    totalPage() {
      return Math.ceil(this.articlesCount / this.limit);
    },
  },
  methods: {
    async onFavorite(article) {
      article.favoriteDisabled = true
      if (!article.favorited){
        await addFavorite (article.slug)
         article.favoritesCount += 1
      } else {
        await delFavorite (article.slug)
        article.favoritesCount  -= 1
      }
      article.favorited = !article.favorited;
      article.favoriteDisabled = false
    },
  },
};
</script>
